"A lolcat is an image combining a photograph, most frequently a cat, with a humorous and idiosyncratic caption in (often) broken English—a dialect which is known as 'lolspeak', or 'Kitteh!'. The name 'lolcat' is a compound word of 'LOL' and 'cat'."

Learn to speak lolspeak, "teh furst language born of teh intertubes."